STM32 Fiend

STM32 Fiend V0.2 and V0.3 render

What is it?

This is a small (1.2" x 0.7") board with an STM32F042F6 MCU, 3.3V regulator,
USB mini-B, reset and boot buttons, TX and RX LEDs, SWD header and all I/O pins
brought out to SIP headers. This board is pin and form-factor similar to the
commonly used FTDI Friend board and provides a pin-compatible serial connector.
It also provides additional connectors for other interfaces, such as SPI, I2C
and SWD programming. Additionally, the main serial connector pins support
digital GPIO, 12-bit analog input, touch sensing and various timer functions
such as PWM. With this board and some custom programming you can build
simple and inexpensive USB-based communications and control applications.

What it isn't

This is not a full development system - you'll have to gather your own
programming tools, power supply, I/O devices, etc. This is not an Arduino
clone with all the low-level stuff already done for you. If you want to get by
on the cheap you'll have to be familiar with setting up an ARM GCC toolchain
as well as using a JTAG/SWD debugger.

Software Development

The STM32 family of parts are supported by a variety of commercial IDEs, all
of which are available in low-cost or limited free versions from the
ST website.

I prefer to use open-source tools so I've set up a development environment
based on the GNU C compiler for ARM, available for free from the Launchpad
project. For downloading to the target I use OpenOCD and the ST-Link V2 SWD
interface that's available on most all of the inexpensive STM32 Discovery boards.
To accelerate development I also use the STM32 Standard Peripheral Library as
a starting point for my code and then optimize out the heavyweight functions
as required. Links to all of these are here: